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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Balancing Grief and Survival: Grounded Theory Analysis of Experiences of Children with Brain Tumours and Their Parents

Eaton Russell, Ceilidh 03 January 2014 (has links)
While researchers have explored many important aspects of living with childhood cancer, including the multitude of strains on family members and their reactions, very little is known about the experiences of children with brain tumours and their parents. Grounded theory methods were utilized to explore the unique and shared elements of the experiences of childhood brain tumours, from the perspectives of these children and their parents. Woven throughout their stories were expressions of grief and uncertainty related to the tumour and its effects on their lives. Children and parents tried to maintain a positive outlook and a sense of normalcy, in order to cope and to adapt to the struggles and the changes in their lives. A substantive theory of Balancing Grief and Survival was developed, offering a lens through which to view the children’s and parents’ complex experiences, struggles and coping strategies as integrated, dynamic processes.
12

Who cares for the caregiver? How are the needs of caregivers of primary malignant brain tumour patients met through structured neuro-oncology programs in Canadian Centres?

Reuter, Orit 23 November 2011 (has links)
This qualitative multi case research asks how the needs of caregivers of primary malignant brain tumour (PMBT) patients are met through structured neuro-oncology programs in Canadian centres. Utilizing telephone interviews with eleven social workers and one psychologist the study analyses their perspectives on the scope and nature of services to brain tumour patients and their caregivers. PMBT is a rare and palliative disease often with neurocognitive and neurobehavioral effects posing special challenges for caregivers. Health care system reliance on family caregivers has resulted in significant implications for their emotional and physical risk. Findings show exclusive patient focused health care in ambulatory programs with fragmented care resulting in marginalization and invisibility of caregivers. This approach is inconsistent with current literature promoting collaborative family centered care, recommended for continuity of care throughout the illness trajectory. Recommendations focus on systemic caregiver service improvements.
13

Who cares for the caregiver? How are the needs of caregivers of primary malignant brain tumour patients met through structured neuro-oncology programs in Canadian Centres?

Reuter, Orit 23 November 2011 (has links)
This qualitative multi case research asks how the needs of caregivers of primary malignant brain tumour (PMBT) patients are met through structured neuro-oncology programs in Canadian centres. Utilizing telephone interviews with eleven social workers and one psychologist the study analyses their perspectives on the scope and nature of services to brain tumour patients and their caregivers. PMBT is a rare and palliative disease often with neurocognitive and neurobehavioral effects posing special challenges for caregivers. Health care system reliance on family caregivers has resulted in significant implications for their emotional and physical risk. Findings show exclusive patient focused health care in ambulatory programs with fragmented care resulting in marginalization and invisibility of caregivers. This approach is inconsistent with current literature promoting collaborative family centered care, recommended for continuity of care throughout the illness trajectory. Recommendations focus on systemic caregiver service improvements.
14

Segmentace nádorů mozku v MRI datech s využitím hloubkového učení / Segmentation of brain tumours in MRI images using deep learning

Ustsinau, Usevalad January 2020 (has links)
The following master's thesis paper equipped with a short description of CT scans and MR images and the main differences between them, explanation of the structure of convolutional neural networks and how they implemented into biomedical image analysis, besides it was taken a popular modification of U-Net and tested on two loss-functions. As far as segmentation quality plays a highly important role for doctors, in experiment part it was paid significant attention to training quality and prediction results of the model. The experiment has shown the effectiveness of the provided algorithm and performed 100 training cases with the following analysis through the similarity. The proposed outcome gives us certain ideas for future improving the quality of image segmentation via deep learning techniques.
15

Incremental Learning approaches to Biomedical decision problems

Tortajada Velert, Salvador 21 September 2012 (has links)
During the last decade, a new trend in medicine is transforming the nature of healthcare from reactive to proactive. This new paradigm is changing into a personalized medicine where the prevention, diagnosis, and treatment of disease is focused on individual patients. This paradigm is known as P4 medicine. Among other key benefits, P4 medicine aspires to detect diseases at an early stage and introduce diagnosis to stratify patients and diseases to select the optimal therapy based on individual observations and taking into account the patient outcomes to empower the physician, the patient, and their communication. This paradigm transformation relies on the availability of complex multi-level biomedical data that are increasingly accurate, since it is possible to find exactly the needed information, but also exponentially noisy, since the access to that information is more and more challenging. In order to take advantage of this information, an important effort is being made in the last decades to digitalize medical records and to develop new mathematical and computational methods for extracting maximum knowledge from patient records, building dynamic and disease-predictive models from massive amounts of integrated clinical and biomedical data. This requirement enables the use of computer-assisted Clinical Decision Support Systems for the management of individual patients. The Clinical Decision Support System (CDSS) are computational systems that provide precise and specific knowledge for the medical decisions to be adopted for diagnosis, prognosis, treatment and management of patients. The CDSS are highly related to the concept of evidence-based medicine since they infer medical knowledge from the biomedical databases and the acquisition protocols that are used for the development of the systems, give computational support based on evidence for the clinical practice, and evaluate the performance and the added value of the solution for each specific medical problem. / Tortajada Velert, S. (2012). Incremental Learning approaches to Biomedical decision problems [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/17195
16

Potential novel targets for treatment of malignant glioma

Bryan Day Unknown Date (has links)
No description available.
17

A clinicopathological and molecular genetic analysis of low-grade glioma in adults

Singh, Anushree January 2014 (has links)
The aim of the study was to identify molecular markers that can determine progression of low grade glioma. This was done using various approaches such as IDH1 and IDH2 mutation analysis, MGMT methylation analysis, copy number analysis using array comparative genomic hybridisation and identification of differentially expressed miRNAs using miRNA microarray analysis. IDH1 mutation was present at a frequency of 71% in low grade glioma and was identified as an independent marker for improved OS in a multivariate analysis, which confirms the previous findings in low grade glioma studies. IDH1 mutation was associated with MGMT promoter methylation when partially methylated tumours were grouped with methylated tumours. Grade II and grade III tumour comparison analysis revealed 14 novel significant miRNAs with differential expression. A miRNA signature was shown for histological subtypes, oligoastrocytoma and anaplastic oligoastrocytoma, following the miRNA expression analysis in grade II and grade III tumors based on histology. Oligoastrocytoma presented a more similar profile to oligodendroglioma, but anaplastic oligoastrocytoma was more similar to anaplastic astrocytoma. Five novel miRNAs were identified in grade III tumours, when comparing IDH1 mutant and IDH1 wild type tumours. Analysis of paired samples of primary/recurrent tumours revealed that additional genomic changes may promote tumour progression. For each of the pair, the two samples were genomically different and in each case, the reccurent tumours had more copy number aberrations than the corresponding primary tumours. Cell cultures derived from the tumour biopsies were not representative of the low grade glioma in vivo, which was evident from the differences identified in the miRNA expression and copy number changes in the paired samples. IDH1 mutation present in tumour biopsies was not maintained in their respective cell cultures. These findings give an insight into the molecular mechanisms involved in the tumourigenesis of low grade glioma and also tumour progression.
18

Gene polymorphisms influencing the cause and disease outcome of childhood central nervous system tumours

Ferguson, Anthea Elizabeth, Women's & Children's Health, Faculty of Medicine, UNSW January 2009 (has links)
Tumours of the central nervous system (CNS) are the second most common cancers diagnosed in children, yet the cause of this disease remains largely unknown. This thesis examines whether polymorphisms in folate-metabolising and glutathione S transferase (GST) genes influence the risk and disease outcome of childhood CNS tumours. 204 children aged ≤18 years diagnosed with a CNS tumour at the Sydney Children??s Hospital between 1989 and 2004 were included in the study. DNA samples were isolated from archival frozen and formalin-fixed paraffin-embedded tumour tissue. Polymorphisms in GST and folate pathway genes were examined using real-time PCR. Genotype distributions in children with CNS tumours were compared to those observed in a control panel of cord blood samples from 363 healthy newborns. Children carrying at least one variant allele for each of MTHFR 677 C>T, MTHFR 1298 A>C, MTR 2756 A>G, MTRR 66 A>G, and RFC 80 G>A were found to have a 2.8-fold greater risk of developing a CNS tumour than non-carriers (OR=2.80; 95%CI: 1.08-7.56, P=0.022), an association which was even more apparent in those children with an embryonal tumour (OR=4.54; 95%CI: 1.13-15.85, P=0.016). Results also showed that children with the GSTP1 105 Val/Val genotype were three times more likely to develop a CNS tumour of embryonal cell origin than children with the GSTP1 105 Ile/Ile or Ile/Val genotypes (OR=3.02; 95%CI: 1.34-6.46, P=0.005). No such association was observed for CNS tumours of glial cell origin. The GSTM1, GSTT1, and GSTP1 Ala114Val polymorphisms did not appear to be associated with the development of a childhood CNS tumour. In addition, children with the MTHFR 677 TT or RFC 80 AA genotypes were found to have a higher risk of death within 5 years of diagnosis compared to children with one or more MTHFR 677 C or RFC 80 G alleles, respectively (HR=5.52, 95%CI: 1.00-30.37, P=0.049 and HR=5.69, 95%CI: 1.38-23.51, P=0.016, respectively), after adjusting for other prognostic factors such as sex, age at diagnosis, period of diagnosis, and tumour grade. Conversely, children with the MTR 2756 AG or GG genotypes, or MTRR 66 AG or GG genotypes, were more likely to survive compared to those with the MTR 2756 AA or MTRR 66 AA genotypes, respectively (HR=0.21, 95%CI: 0.05-0.93, P=0.040 and HR=0.11, 95%CI: 0.02-0.53, P=0.006). Results presented in this thesis indicate that polymorphisms in folate-metabolising and GST genes may play a role in the aetiology and survival of childhood CNS tumours, and that this may vary depending on the histological sub-type of tumour.
19

Wnt Signaling in Human Neural Stem Cells and Brain Tumour Stem Cells

Brandon, Caroline 15 December 2010 (has links)
We sought to determine whether activation of the Wnt signaling pathway altered the function of hNSCs in vitro. We took three approaches to activate Wnt signaling: Wnt3a, constitutively stabilized β-catenin (ΔN90), and the GSK3 inhibitor BIO. While Wnt3a and ΔN90 had no effect on proliferation in both stem cell (+EGF/FGF) and differentiating (-EGF/FGF) conditions, BIO reduced proliferation in both. All methods of Wnt signaling activation promoted neuronal lineage commitment during hNSC differentiation. Furthermore, BIO was able to induce mild neuronal differentiation in stem cell conditions, suggesting that GSK3-inhibition interferes with several pathways to regulate hNSC fate decisions. We also probed BTSC function using BIO-mediated GSK3 inhibition. We found that in stem cell conditions, BIO was able to induce neuronal differentiation, decrease proliferation, and induce cell cycle arrest. Together this data suggests that GSK3-inhibition, possibly through activation of Wnt signaling, may offer a novel mechanism for the differentiation treatment of glioblastomas.
20

Wnt Signaling in Human Neural Stem Cells and Brain Tumour Stem Cells

Brandon, Caroline 15 December 2010 (has links)
We sought to determine whether activation of the Wnt signaling pathway altered the function of hNSCs in vitro. We took three approaches to activate Wnt signaling: Wnt3a, constitutively stabilized β-catenin (ΔN90), and the GSK3 inhibitor BIO. While Wnt3a and ΔN90 had no effect on proliferation in both stem cell (+EGF/FGF) and differentiating (-EGF/FGF) conditions, BIO reduced proliferation in both. All methods of Wnt signaling activation promoted neuronal lineage commitment during hNSC differentiation. Furthermore, BIO was able to induce mild neuronal differentiation in stem cell conditions, suggesting that GSK3-inhibition interferes with several pathways to regulate hNSC fate decisions. We also probed BTSC function using BIO-mediated GSK3 inhibition. We found that in stem cell conditions, BIO was able to induce neuronal differentiation, decrease proliferation, and induce cell cycle arrest. Together this data suggests that GSK3-inhibition, possibly through activation of Wnt signaling, may offer a novel mechanism for the differentiation treatment of glioblastomas.

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